Nicotinic acetylcholine receptor involvement in inflammatory bowel disease and interactions with gut microbiota

The gut-brain axis describes a complex interplay between the central nervous system and organs of the gastrointestinal tract. Sensory neurons of dorsal root and nodose ganglia, neurons of the autonomic nervous system, and immune cells collect and relay information about the status of the gut to the brain. A critical component in this bi-directional communication system is the vagus nerve which is essential for coordinating the immune system’s response to the activities of commensal bacteria in the gut and to pathogenic strains and their toxins. Local control of gut function is provided by networks of neurons in the enteric nervous system also called the ‘gut-brain’. One element common to all of these gut-brain systems is the expression of nicotinic acetylcholine receptors. These ligand-gated ion channels serve myriad roles in the gut-brain axis including mediating fast synaptic transmission between autonomic pre-and postganglionic neurons, modulation of neurotransmitter release from peripheral sensory and enteric neurons, and modulation of cytokine release from immune cells. Here we review the role of nicotinic receptors in the gut-brain axis with a focus on the interplay of these receptors with the gut microbiome and their involvement in dysregulation of gut function and inflammatory bowel diseases

Gut–brain axis in the executive function of austism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by impaired communication and social interactions, and repetitive behavioural patterns. These patterns are believed to be dysfunctional symptoms in executive processing, which impact other cognitive functions such as attention or cognitive flexibility. In recent years, several studies have shown that certain intestinal bacteria may play a role in shaping cognitive networks encompassing emotional and social domains. A microbiota–gut–brain axis is known to exist, establishing several mechanisms by which microbiota may modulate brain development, function and behaviour, including immune, endocrine and neural pathways. As the aetiology of ASD is largely unknown, some studies have shown that intestinal bacteria may be involved in its pathogenesis. The aim of this review was to focus on the role of the gut–brain axis in ASD and, specifically, on its role in executive functions. First, we summarize the relationship between the gastrointestinal and cognitive symptoms of ASD patients. In addition, we highlight the evidence that supports and emphasizes the involvement of gut microbiota, and the putative underlying mechanisms in this population. Finally, we present evidence from preclinical and clinical studies on the modulation of microbiota and their effects on cognitive symptoms, specifically in relation to executive function. In conclusion, manipulation of microbiota could be a positive intervention to improve ASD symptoms. However, more research evaluating the role of microbiota in the cognitive symptoms ASD is needed

Effects of probiotics supplementation on dementia and cognitive impairment: A systematic review and meta-analysis of preclinical and clinical studies

Background Dementia is a chronic syndrome characterized by cognitive and behavioral symptoms, which may include short-term memory impairment and problems related to orientation, language, attention and perception. Although cognitive impairment (CI) is increasingly considered the main geriatric condition predisposing to dementia, its early management could still promote symptomatic relief and delay disease progression. Recently, probiotics treatment has been studied as a potential new therapeutic approach to attenuate dementia-related decline and mild cognitive impairment (MCI). Therefore, we conducted a systematic review and meta-analysis to review and analyse the available evidence on the effect of probiotics on MCI and dementia. Methods A systematic search and meta-analysis were performed on Cochrane Library, ProQuest, Web of Science, PubMed-Medline, The Cumulative Index to Nursing and Allied Health Literature (CINAHL), Scopus, ScienceDirect and Open Grey. Search terms included diagnoses of interest (dementia and MCI) and the intervention of interest (probiotic, lactobacillus and bifidobacterium). Original articles reporting the use of probiotics supplementation for the treatment of dementia and MCI were screened and studied independently by two researchers. After that, a random and fixed effects model was used at the meta-analysis stage of the results to determine its effect size. Results A total of 16 articles (10 preclinical and 6 clinical) that met the inclusion criteria for the systematic review, and 15 articles (10 preclinical and 5 clinical) for meta-analysis were finally included. In humans, the administration of probiotics improved general cognitive function after the treatment period. Similarly, an improvement in memory and spatial/non-spatial learning was identified in the probiotic group of animals compared to the control group. On the other hand, the results showed an increase in the levels of the brain-derived neurotrophic factor, an improvement in the inflammatory profile and regulation of cellular biomarkers after probiotics administration. Conclusion Probiotics supplementation could be an adequate therapeutic strategy both in dementia and CI based on clinical and preclinical evidence. However, it is therefore important to translate preclinical data into clinical data where the evidence is more limited

Central nervous system stimulation therapies in phantom limb pain: a systematic review of clinical trials

Phantom limb pain is a chronic pain syndrome that is difficult to cope with. Despite neurostimulation treatment is indicated for refractory neuropathic pain, there is scant evidence from randomized controlled trials to recommend it as the treatment choice. Thus, a systematic review was performed to analyze the efficacy of central nervous system stimulation therapies as a strategy for pain management in patients with phantom limb pain. A literature search for studies conducted between 1970 and September 2020 was carried out using the MEDLINE and Embase databases. Principles of The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline were followed. There were a total of 10 full-text articles retrieved and included in this review. Deep brain stimulation, repetitive transcranial magnetic stimulation, transcranial direct current stimulation, and motor cortex stimulation were the treatment strategies used in the selected clinical trials. Repetitive transcranial magnetic stimulation and transcranial direct current stimulation were effective therapies to reduce pain perception, as well as to relieve anxiety and depression symptoms in phantom limb pain patients. Conversely, invasive approaches were considered the last treatment option as evidence in deep brain stimulation and motor cortex stimulation suggests that the value of phantom limb pain treatment remains controversial. However, the findings on use of these treatment strategies in other forms of neuropathic pain suggest that these invasive approaches could be a potential option for phantom limb pain patients

Probiotics as a therapeutic strategy in obesity and overweight: a systematic review

Obesity and overweight are two of the most health challenges with an increasing prevalence in recent years, in which several complications have been identified to have a high impact in patients’ health conditions. In this vein, an increasing interest in the gut microbiota has emerged as a target for therapeutic strategies in obesity and overweight due to its direct relation with the aforementioned health conditions and complications. Thus, the aim of this study was to evaluate the efficacy of probiotics as a therapeutic strategy in the management of obesity and overweight. A systematic review of randomised controlled trials was carried out in 6 databases until May 2019 to assess the use of probiotics in obesity and overweight patients. The Jadad Scale was used to assess the quality of the clinical trials. Twenty-three clinical trials published between 2000 and 2019 met the inclusion criteria. The role of probiotics in reducing body mass index and weight as well as changing the visceral abdominal fat area, waist and hip circumference were shown in 14 of 23 trials (60.87%); 14 trials (60.87%) showed changes on patients’ fatty acids and biomarkers; and 4 trials (17.39%) studied the role of the gut microbiota in obese and overweight patients. Some probiotics strains are shown to be effective in reducing body mass index and hip circumference. This review provides evidence of successful results in weight loss using probiotic groups

Impact of Cervical Cancer on Quality of Life and Sexuality in Female Survivors

Cervical cancer is the fourth most frequent cancer in women worldwide, and the 11th most frequent neoplasm in Spain. Despite the optimization of treatments and a 5-year survival rate of 70%, side effects and sequelae are described after treatment. The treatments have physical, psychological and sociocultural consequences that deteriorate the quality of life of patients. One of the sequelae that worries patients is the impairment of sexual function and satisfaction, considered a fundamental dimension of the human being. The aim of this study was to examine quality of life and sexual function and satisfaction among Spanish cervical cancer survivors. A retrospective case-control study was conducted between 2019 and 2022. The sample consisted of 66 patients who completed the Female Sexual Function Index, the Golombok Rust Sexual Satisfaction Inventory and European Organization for Research and Treatment of Cancer quality of life questionnaire. The control group consisted of women without cervical cancer and gynecological pathologies obtained using the so-called online virtual sampling method. The patient group consisted of women with cervical cancer who completed treatment. Cervical cancer survivors reported sexual dysfunction and impaired sexual satisfaction in almost half of the domains. Quality of life was also affected, with pain and fatigue being the most frequent symptoms in these patients. Our results indicate that there is dysfunction, sexual dissatisfaction and a lower level of quality of life in cervical cancer survivors than in healthy women without pathology

Effects of probiotics on cognitive and emotional functions in healthy older adults: Protocol for a double-blind randomized placebo-controlled crossover trial

Aging is a process that includes changes in cognitive and emotional functions,as well as changes in the diversity and integrity of gut microbiota. Probiotictreatments have recently been studied as a potential new therapeutic approachto alleviate a wide range of problems in other populations; however, clinicalstudies in older adults remain insufficient and limited. Thus, the aim of thisproject is to evaluate the efficacy of a multispecies probiotic formulation as atherapeutic strategy for attenuating the emotional and cognitive decline asso-ciated with aging in adults over the age of 55. This is a double‐blind randomizedplacebo‐controlled crossover trial involving at least 32 older adults andcomparing two conditions: (a) probiotic, providing a multispecies probiotic for10 weeks (Lactobacillus rhamnosusandBifidobacterium lactis); and (b) placebo,receiving a harmless substance (potato starch). Despite the increasing use ofprobiotics for the treatment of cognitive and emotional problems, no study hasyet focused on this group, to the best of our knowledge. Therapeutic strategiesof the kind outlined in this protocol will help to shed light on the current state ofknowledge about this topic, as well as promote health programs tailored to thispopulation, which would encourage active aging and healthy lifestyles. Not onlydo we expect improvements in the emotional dimension in terms of anxiety,stress, depression, and sleep quality, we also expect improvements in the cog-nitive dimension in terms of attention,memory, and decreased impulsivity

Therapeutic concentrations of varenicline increases exocytotic release of catecholamines from human and rat adrenal chromaffin cells in the presence of nicotine

Cardiovascular side effects of varenicline and a case report of a hypertensive crisis in a varenicline-prescribed patient with pheochromocytoma have been reported. The goal of the present study was to determine whether such side effects might derive, in part, from increased exocytosis of secretory vesicles and subsequent catecholamine release triggered by varenicline in human chromaffin cells of the adrenal gland. In this study, we performed electrophysiological plasma membrane capacitance and carbon fiber amperometry experiments to evaluate the effect of varenicline on exocytosis and catecholamine release, respectively, at concentrations reached during varenicline therapy (100 nM). Experiments were conducted in the absence or presence of nicotine, at plasma concentrations achieved right after smoking (250 nM) or steady-state concentrations (110 nM), in chromaffin cells of the adrenal gland obtained from human organ donors. Cells were stimulated with short pulses (10 ms) of acetylcholine (ACh; 300 μM) applied at 0.2 Hz, in order to closer mimic the physiological situation at the splanchnic nerve-chromaffin cell synapse. In addition, rat chromaffin cells were used to compare the effects obtained in cells from a more readily available species. Varenicline increased the exocytosis of secretory vesicles in human and rat chromaffin cells in the presence of nicotine, effects that were not due to an increase of plasma membrane capacitance or currents triggered by the nicotinic agonists alone. These results should be considered in nicotine addiction therapies when varenicline is usedThis work was supported by grants from the Spanish Ministry of Science and Innovation [grant number BFU2015-69092 to A.A.] and the U.S. National Institutes of Health [GM136430 and GM103801 to J.M.M

The Influence of Cannabis and Alcohol Use on Sexuality: An Observational Study in Young People (18–30 Years)

The consumption of cannabis and alcohol results in a variety of effects on the psychic functions of young users. Notwithstanding their widespread and prevalent use, the impact of these drugs on sexual health remains unknown. Thus, the aim of this study is to analyse the influence of alcohol and cannabis consumption on sexual function in young people. An observational study was conducted in 274 participants aged 18–30 years. The following selection tools were used: Alcohol Use Disorders Identification Test, Cannabis Abuse Screening Test (CAST), and Changes in Sexual Functioning Questionnaire Short-Form. Participants who were at high risk of having cannabis-related problems performed better on the CAST concerning sexual function, arousal, and orgasm. Participants at high risk had higher arousal and orgasm scores than those who were not at risk for cannabis problems. Improvements in sexual function were found between people who were at high risk of having alcohol problems and those who were not at risk. Sexual function in young people who use cannabis and alcohol more frequently was shown to be better than in those who do not use either, highlighting the need for more information aimed at the young population

Influence of Shift Work on The Health of Nursing Professionals

Shift work is increasingly common in health services, subjecting healthcare professionals to work schedules that can alter circadian rhythms and eating habits with consequent repercussions for the intestinal homeostasis. The objective of this study was to describe the relationship of rotating work shifts with the intestinal health, sleep quality, and emotional dimension of nursing professionals. In March and May 2019, an observational and comparative study was conducted among 380 nursing professionals from different Spanish cities and divided into fixed shift (n = 159) and rotating shift (n = 221). To carry out the present work, the variables measured were gastrointestinal symptoms, stool consistency and shape, anxiety, depression, sleep, as well as stress and work environment. Nurses with rotating shifts reported more abdominal pain and symptoms of depersonalization, as well as worse sleep efficiency and worse nursing practice environment. In addition, overall scores of the Gastrointestinal Symptom Rating Scale and Hospital Anxiety and Depression Scale were found to be significantly worse in nurses with these shifts. Rotating shift work by nursing staff may be associated with the occurrence of gastrointestinal and anxiety-related symptoms. These findings, together with the presence of negative and insensitive attitudes towards patients by nurses on rotating shifts, should be considered to maintain the quality of healthcare